The present invention relates to a construction of a mini-motor and a method of assembling the mini-motor at high productivity. More particularly, the present invention relates to a micro-motor producing vibration sensible to a human body. This micro-motor is employed in a cellular-phone to notify a user of a call with the vibration.
A motor used in information devices comprises the following elements:
a metal base;
a bearing, a printed circuit board, and a stator mounted to the metal base;
a cylindrical rotor magnet mounted on an outer or inner wall of the stator core, thereby facing the magnet to the stator core.
When a motor has a certain size, this structure is easy to assemble; however, downsizing the motor increases difficulties of assembling and lowers the productivity, because assembling machines or operators"" finger-tips cannot access to inside or even cannot access close to the motor.
The Japanese Patent Application Non-Examined Publication No. H10-127031 addresses the problem discussed above. FIG. 10 illustrates the motor of this prior art.
In FIG. 10, metal wired-board 14 is buried in base 24 made of synthetic resin with maintaining the insulation. A first end of board 14 extends over an upper end of base 24 as riser 40, and a second end is exposed as a connector terminal.
This structure allows terminal 42 of winding 18 coiled on stator core 20 to be coupled to riser 40 with ease.
However, downsizing the motor reveals a problem, i.e. elements of the motor are hard to handle by operators. For instance, a motor of 10 mm across gives us a difficulty to handle its components quickly. Further downsizing of the motor requires severer mating allowances between the components. This increases the difficulty of assembling the components into a motor. As such, the productivity is traded off for downsizing the motor. A breakthrough method of this problem has been enthusiastically demanded.
A section bonded with another section or a section undergone resin-welding needs time before it is fixed to. Shortening this waiting time has been also demanded.
The present invention addresses the problems discussed above, and aims to provide a motor having a structure allowing high productivity as well as a method of assembling the same motor by solving problems such as difficulty of handling, severity of mating, time-consuming of bonding or welding.
A motor-base-holder of the present invention comprises the following elements:
(a) a motor base including;
(a-1) a base;
(a-2) a bearing supporter protruded vertically from the base for supporting a bearing;
(a-3) a stator supporter concentric with the bearing supporter for being mounted with a stator;
(a-4) a terminal made of metal plate and insert-molded around the bearing supporter;
(b) a frame made of the same metal as the terminal and linked with fringe section of the motor base
A motor of the present invention comprises the following elements:
(a) a motor base including;
(a-1) a base;
(a-2) a bearing supporter protruded vertically from the base for supporting a bearing;
(a-3) a stator supporter concentric with the bearing supporter;
(a-4) a terminal made of metal plate and insert-molded around the bearing supporter;
The motor base is formed by cutting off bridges linking between the motor base and the frame around the motor base.
(b) a stator mounted to the stator supporter; and
(c) a rotor supported by the bearing which is supported by the bearing supporter.
Another motor of the present invention comprises the following elements:
(a) a stator having a stator core;
(b) a motor base including:
(b-1) a base;
(b-2) a bearing supporter protruded vertically from the base for supporting a bearing;
(b-3) a stator supporter concentric with the bearing supporter;
(b-4) a stator fixer extending from the stator supporter; and
(c) a rotor supported by the bearing supported by the bearing supporter.
After the stator core is inserted into the stator supporter, a bushing is press-fitted into the stator fixer, thereby fixing the stator.
Still another motor of the present invention comprises the following elements:
(a) a motor base including:
(a-1) a base;
(a-2) a bearing supporter protruded vertically from the base for supporting a bearing;
(a-3) a stator supporter;
(a-4) a terminal made of metal plate and disposed around the bearing supporter;
(a-5) a metal tip extended outside of the motor base;
(b) a stator mounted to the stator supporter;
(c) a rotor supported by the bearing which is supported by the bearing supporter; and
(d) a metal cover of which terminal is fixed to the metal tip, for covering the rotor.
The motor discussed above may be assembled through the following steps:
(a) positioning and supporting the motor base at a given place by the frame;
(b) assembling the stator and the rotor to the motor base; and
(c) detaching the motor base from the frame.
The present invention discussed above can solve the problems particularly in mini-motors such as difficulties in handling the parts of the motor, difficulties in mating the respective components, time-consuming of bonding or welding. As a result, a motor of high productivity and a method of assembling the motor can be obtained.